Industrial Processes Needing High Heat- An Overview

Vinod NarayananUniversity of California- Davis

UC Solar Thermal SymposiumNovember 15th 2019

Setting the stage- US Manufacturing Energy Consumption (2014 MECS)

• Fuel use is 4.5 times larger than electricity use

• NG is the predominant fuel

• Significant part of process heat is driven by steam

• Total emissions: 1064 MMT CO2e (16% of US total)

Setting the stage- Natural Gas use in US

Industrial processes used 10.04 trillion cubic feet (~34%) of natural gas 2018

5 largest NG consuming states:TX (14.3%)CA (7.8%)LA (5.9%)FL (5.1%)PA (4.7%)

Setting the stage- Top thermal energy consumption industries (TBtu)

US*

Wes

tern

cen

sus r

egio

n*

Western region accounts for ~12% of total industrial natural gas consumption

*Source for US and western region: 2014 MECS data**Source for CA data: California Energy Commission, 2019, “Research Roadmap for Advancing technologies in California’s Industrial, Agriculture and Water Sectors,” Energy Research and Development division Final Project Report CEC-500-2019-016

Subsector and industryNet

Electricity Natural

Gas O&G extraction and mining support 22.02 230.54Petroleum and coal products manufacturing 28.90 184Chemicals 1.34 39.3Food and beverage 20.24 37.7Primary metals 0.51 9.7

Subsector and IndustryNet

ElectricityNatural

GasPetroleum and Coal Products 26 261Petroleum Refineries 25 249

Food 41 135Chemicals 39 63Paper 34 61Fruit and Vegetable Preserving and Specialty Food 12 60Nonmetallic Mineral Products 20 47Primary Metals 47 35

Cal

iforn

ia**

Subsector and IndustryNet

ElectricityNatural

GasChemicals 458 2496Petroleum and Coal Products 167 1072Petroleum Refineries 160 1000

Primary Metals 433 688Food 247 572Other Basic Organic Chemicals 57 474Iron and Steel Mills and

Ferroalloys 204 443Paper 191 436Plastics Materials and Resins 58 424Nitrogenous Fertilizers 13 383

Oil and Gas Extraction (upstream)

• driving pumps to extract hydrocarbons and to reinject water;

• Enhanced oil recovery- thermal injection (40% of CA oil)• heating the output stream to allow separation of the oil, gas

and water; • powering compressors and pumps for transporting oil and

gas through gathering pipelines to processing plants; • driving turbines to generate the electricity and heat needed

for on-site operations

Sources:IPIECA, 2013, Saving Energy in the oil and gas industry

Solar Enhanced Oil recovery could displace 20% of NG use for EOR in CA: Kern County 21Z Solar Project (GlassPoint Solar)

Petroleum Refining (Downstream)

• Fractional distillation• Rearrangement of HC molecules- Conversion of paraffins to aromatics

(dehydrogenation and aromatization), longer chains to aromatics and branched HCs (isomerization); goal- higher octane value, longer chains broken into smaller molecules (cracking)

Source: Appendix - McMilan et al., 2016, Generation and use of thermal energy in the US Industrial Sector and Opportunities to Reduce its Carbon Emissions,NREL/TP-6A50-66763, INL/EXT-16-39680

Typical refinery energy and product flows

Chemical Manufacturing (2004 data)

• Chemical processing -Two main steps-• Primary synthesis• Separation and purification (fractional distillation)

• 40% of heat in chemical plants is delivered using steam• Final products- soaps, cleaners, bleach, cosmetics, dyes, pharmaceuticals, plastics• Intermediate products – plastics, rubber, textiles, apparel, paper• CA- pharmaceuticals, soaps and cleaners, inorganic chemicals make up 75% of CA

industry

C. Garitsky, E. Worrell, 2004, Profile of the Chemicals Industry in California-California Industries of the Future Program, LBNL 55668

CA chemicals industry (2000)

Petrochemicals

Feedstock for polyethylene (~60% used for this); rest used in ethylene glycol, industrial ethanol, …

https://www.acs.org/content/acs/en/pressroom/cutting-edge-chemistry/beyond-the-ethylene-steam-cracker.html

Source: Appendix - McMilan et al., 2016, Generation and use of thermal energy in the US Industrial Sector and Opportunities to Reduce its Carbon Emissions,NREL/TP-6A50-66763, INL/EXT-16-39680

Lime (CaO) production

• Lime is used as an alkaline agent • Iron and steel, pulp and paper, treatment of flue gas and water; key ingredient of

cement• Large rotary kiln at 900-1200 oC (endothermic)

CaCO3.MgCO3+ heat --> 2CO2 + CaO.MgO (dolomitic lime)

CaCO3 (s) CaO (s)+CO2 (g)

Source: Appendix - McMilan et al., 2016, Generation and use of thermal energy in the US Industrial Sector and Opportunities to Reduce its Carbon Emissions,NREL/TP-6A50-66763, INL/EXT-16-39680

Cement Production

• Grinding a mixture of limestone and clay or shale to make a fine “rawmix” • Heating the rawmix to sintering temperature (up to 1,500°C) in a cement kiln – heat source at 1800-

2000 C• Kiln fired by combustion of coal, petroleum coke, heavy fuel oil, natural gas, landfill off-gas, and oil

refinery flare gas (used tires!)• Radiation heat transfer dominant• Grinding the resulting clinker to make cement.

Source: Appendix - McMilan et al., 2016, Generation and use of thermal energy in the US Industrial Sector and Opportunities to Reduce its Carbon Emissions,NREL/TP-6A50-66763, INL/EXT-16-39680

Fertilizer Production (Ammonia synthesis)

Typical fertilizer plant energy and product flows

• 9.4 million tons in US (2015); accounts for 88% of NH3 use

• Constituents- natural gas- for H2; air for N2

Source: Appendix - McMilan et al., 2016, Generation and use of thermal energy in the US Industrial Sector and Opportunities to Reduce its Carbon Emissions,NREL/TP-6A50-66763, INL/EXT-16-39680

Food Processes that Use Heat

• Pasteurization & sterilization• Concentration

sorting tomatoes

Skin removal with steam dicer Scraped surface

heat exchanger

Send through hold tubes to sterilize (215 deg F)

Cooling to 90F in counterflow tube-

in-tube HX

Concluding thoughts

• Can solar thermal displace a significant fraction of the NG needed for industrial needs? • What are the competing technologies?• Which application is the “lowest hanging fruit” for solar thermal?

CementLimeAmmonia/FertilizerSteam EORFood & beverage processing Glass Primary metals